Henry Orombi is one of the clergy boycotting the Lambeth Conference
The Archbishop of Canterbury has been accused of "betrayal" over the issue of gay bishops.
Writing in the Times, the Archbishop of Uganda criticised Dr Rowan Williams for inviting American Church leaders to the current Lambeth Conference.
The Most Rev Henry Orombi said there was an "unrelenting commitment" of the US Church "to bless sinful behaviour".
The Anglican Church has been divided since the ordination of the openly gay bishop Gene Robinson in the US in 2003.
Archbishop Orombi wrote: "In every case, homosexual practice is considered sinful, something that breaks our relationship with God and harms our wellbeing.
"It is something for which one should repent and seek forgiveness and healing, which God is ever ready to do."
He said the ordination of Bishop Robinson was a "deep betrayal".
Archbishop Orombi added: "When the Archbishop of Canterbury invited these American bishops to participate in the Lambeth Conference... in the face of the unrelenting commitment of the American Church to bless sinful behaviour, we were stunned. Further betrayal."
He also said in his article that it was "peculiar" that the Archbishop of Canterbury was not elected by his peers.
"Even the Pope is elected by his peers, but what Anglicans have is a man appointed by a secular government," said the archbishop.
"Over the past five years, we have come to see this as a remnant of British colonialism, and it is not serving us well."
Archbishop Orombi is one of the 250 clergy boycotting the conference over the issue of gay bishops.
Anglican bishops have been discussing Bible teachings on homosexuality at the 10-yearly conference in Canterbury.
However, traditionalists in the Church were frustrated that there was no formal resolution on the issue.